block/scsi_ioctl.c

   1 /*
   2  * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public Licens
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-
  17  *
  18  */
  19 #include <linux/kernel.h>
  20 #include <linux/errno.h>
  21 #include <linux/string.h>
  22 #include <linux/module.h>
  23 #include <linux/blkdev.h>
  24 #include <linux/capability.h>
  25 #include <linux/completion.h>
  26 #include <linux/cdrom.h>
  27 #include <linux/ratelimit.h>
  28 #include <linux/slab.h>
  29 #include <linux/times.h>
  30 #include <linux/uio.h>
  31 #include <asm/uaccess.h>
  32
  33 #include <scsi/scsi.h>
  34 #include <scsi/scsi_ioctl.h>
  35 #include <scsi/scsi_cmnd.h>
  36
  37 struct blk_cmd_filter {
  38         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
  39         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
  40 };
  41
  42 static struct blk_cmd_filter blk_default_cmd_filter;
  43
  44 /* Command group 3 is reserved and should never be used.  */
  45 const unsigned char scsi_command_size_tbl[8] =
  46 {
  47         6, 10, 10, 12,
  48         16, 12, 10, 10
  49 };
  50 EXPORT_SYMBOL(scsi_command_size_tbl);
  51
  52 #include <scsi/sg.h>
  53
  54 static int sg_get_version(int __user *p)
  55 {
  56         static const int sg_version_num = 30527;
  57         return put_user(sg_version_num, p);
  58 }
  59
  60 static int scsi_get_idlun(struct request_queue *q, int __user *p)
  61 {
  62         return put_user(0, p);
  63 }
  64
  65 static int scsi_get_bus(struct request_queue *q, int __user *p)
  66 {
  67         return put_user(0, p);
  68 }
  69
  70 static int sg_get_timeout(struct request_queue *q)
  71 {
  72         return jiffies_to_clock_t(q->sg_timeout);
  73 }
  74
  75 static int sg_set_timeout(struct request_queue *q, int __user *p)
  76 {
  77         int timeout, err = get_user(timeout, p);
  78
  79         if (!err)
  80                 q->sg_timeout = clock_t_to_jiffies(timeout);
  81
  82         return err;
  83 }
  84
  85 static int max_sectors_bytes(struct request_queue *q)
  86 {
  87         unsigned int max_sectors = queue_max_sectors(q);
  88
  89         max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
  90
  91         return max_sectors << 9;
  92 }
  93
  94 static int sg_get_reserved_size(struct request_queue *q, int __user *p)
  95 {
  96         int val = min_t(int, q->sg_reserved_size, max_sectors_bytes(q));
  97
  98         return put_user(val, p);
  99 }
 100
 101 static int sg_set_reserved_size(struct request_queue *q, int __user *p)
 102 {
 103         int size, err = get_user(size, p);
 104
 105         if (err)
 106                 return err;
 107
 108         if (size < 0)
 109                 return -EINVAL;
 110
 111         q->sg_reserved_size = min(size, max_sectors_bytes(q));
 112         return 0;
 113 }
 114
 115 /*
 116  * will always return that we are ATAPI even for a real SCSI drive, I'm not
 117  * so sure this is worth doing anything about (why would you care??)
 118  */
 119 static int sg_emulated_host(struct request_queue *q, int __user *p)
 120 {
 121         return put_user(1, p);
 122 }
 123
 124 static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
 125 {
 126         /* Basic read-only commands */
 127         __set_bit(TEST_UNIT_READY, filter->read_ok);
 128         __set_bit(REQUEST_SENSE, filter->read_ok);
 129         __set_bit(READ_6, filter->read_ok);
 130         __set_bit(READ_10, filter->read_ok);
 131         __set_bit(READ_12, filter->read_ok);
 132         __set_bit(READ_16, filter->read_ok);
 133         __set_bit(READ_BUFFER, filter->read_ok);
 134         __set_bit(READ_DEFECT_DATA, filter->read_ok);
 135         __set_bit(READ_CAPACITY, filter->read_ok);
 136         __set_bit(READ_LONG, filter->read_ok);
 137         __set_bit(INQUIRY, filter->read_ok);
 138         __set_bit(MODE_SENSE, filter->read_ok);
 139         __set_bit(MODE_SENSE_10, filter->read_ok);
 140         __set_bit(LOG_SENSE, filter->read_ok);
 141         __set_bit(START_STOP, filter->read_ok);
 142         __set_bit(GPCMD_VERIFY_10, filter->read_ok);
 143         __set_bit(VERIFY_16, filter->read_ok);
 144         __set_bit(REPORT_LUNS, filter->read_ok);
 145         __set_bit(SERVICE_ACTION_IN, filter->read_ok);
 146         __set_bit(RECEIVE_DIAGNOSTIC, filter->read_ok);
 147         __set_bit(MAINTENANCE_IN, filter->read_ok);
 148         __set_bit(GPCMD_READ_BUFFER_CAPACITY, filter->read_ok);
 149
 150         /* Audio CD commands */
 151         __set_bit(GPCMD_PLAY_CD, filter->read_ok);
 152         __set_bit(GPCMD_PLAY_AUDIO_10, filter->read_ok);
 153         __set_bit(GPCMD_PLAY_AUDIO_MSF, filter->read_ok);
 154         __set_bit(GPCMD_PLAY_AUDIO_TI, filter->read_ok);
 155         __set_bit(GPCMD_PAUSE_RESUME, filter->read_ok);
 156
 157         /* CD/DVD data reading */
 158         __set_bit(GPCMD_READ_CD, filter->read_ok);
 159         __set_bit(GPCMD_READ_CD_MSF, filter->read_ok);
 160         __set_bit(GPCMD_READ_DISC_INFO, filter->read_ok);
 161         __set_bit(GPCMD_READ_CDVD_CAPACITY, filter->read_ok);
 162         __set_bit(GPCMD_READ_DVD_STRUCTURE, filter->read_ok);
 163         __set_bit(GPCMD_READ_HEADER, filter->read_ok);
 164         __set_bit(GPCMD_READ_TRACK_RZONE_INFO, filter->read_ok);
 165         __set_bit(GPCMD_READ_SUBCHANNEL, filter->read_ok);
 166         __set_bit(GPCMD_READ_TOC_PMA_ATIP, filter->read_ok);
 167         __set_bit(GPCMD_REPORT_KEY, filter->read_ok);
 168         __set_bit(GPCMD_SCAN, filter->read_ok);
 169         __set_bit(GPCMD_GET_CONFIGURATION, filter->read_ok);
 170         __set_bit(GPCMD_READ_FORMAT_CAPACITIES, filter->read_ok);
 171         __set_bit(GPCMD_GET_EVENT_STATUS_NOTIFICATION, filter->read_ok);
 172         __set_bit(GPCMD_GET_PERFORMANCE, filter->read_ok);
 173         __set_bit(GPCMD_SEEK, filter->read_ok);
 174         __set_bit(GPCMD_STOP_PLAY_SCAN, filter->read_ok);
 175
 176         /* Basic writing commands */
 177         __set_bit(WRITE_6, filter->write_ok);
 178         __set_bit(WRITE_10, filter->write_ok);
 179         __set_bit(WRITE_VERIFY, filter->write_ok);
 180         __set_bit(WRITE_12, filter->write_ok);
 181         __set_bit(WRITE_VERIFY_12, filter->write_ok);
 182         __set_bit(WRITE_16, filter->write_ok);
 183         __set_bit(WRITE_LONG, filter->write_ok);
 184         __set_bit(WRITE_LONG_2, filter->write_ok);
 185         __set_bit(ERASE, filter->write_ok);
 186         __set_bit(GPCMD_MODE_SELECT_10, filter->write_ok);
 187         __set_bit(MODE_SELECT, filter->write_ok);
 188         __set_bit(LOG_SELECT, filter->write_ok);
 189         __set_bit(GPCMD_BLANK, filter->write_ok);
 190         __set_bit(GPCMD_CLOSE_TRACK, filter->write_ok);
 191         __set_bit(GPCMD_FLUSH_CACHE, filter->write_ok);
 192         __set_bit(GPCMD_FORMAT_UNIT, filter->write_ok);
 193         __set_bit(GPCMD_REPAIR_RZONE_TRACK, filter->write_ok);
 194         __set_bit(GPCMD_RESERVE_RZONE_TRACK, filter->write_ok);
 195         __set_bit(GPCMD_SEND_DVD_STRUCTURE, filter->write_ok);
 196         __set_bit(GPCMD_SEND_EVENT, filter->write_ok);
 197         __set_bit(GPCMD_SEND_KEY, filter->write_ok);
 198         __set_bit(GPCMD_SEND_OPC, filter->write_ok);
 199         __set_bit(GPCMD_SEND_CUE_SHEET, filter->write_ok);
 200         __set_bit(GPCMD_SET_SPEED, filter->write_ok);
 201         __set_bit(GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL, filter->write_ok);
 202         __set_bit(GPCMD_LOAD_UNLOAD, filter->write_ok);
 203         __set_bit(GPCMD_SET_STREAMING, filter->write_ok);
 204         __set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
 205 }
 206
 207 int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
 208 {
 209         struct blk_cmd_filter *filter = &blk_default_cmd_filter;
 210
 211         /* root can do any command. */
 212         if (capable(CAP_SYS_RAWIO))
 213                 return 0;
 214
 215         /* Anybody who can open the device can do a read-safe command */
 216         if (test_bit(cmd[0], filter->read_ok))
 217                 return 0;
 218
 219         /* Write-safe commands require a writable open */
 220         if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
 221                 return 0;
 222
 223         return -EPERM;
 224 }
 225 EXPORT_SYMBOL(blk_verify_command);
 226
 227 static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
 228                              struct sg_io_hdr *hdr, fmode_t mode)
 229 {
 230         if (copy_from_user(rq->cmd, hdr->cmdp, hdr->cmd_len))
 231                 return -EFAULT;
 232         if (blk_verify_command(rq->cmd, mode & FMODE_WRITE))
 233                 return -EPERM;
 234
 235         /*
 236          * fill in request structure
 237          */
 238         rq->cmd_len = hdr->cmd_len;
 239
 240         rq->timeout = msecs_to_jiffies(hdr->timeout);
 241         if (!rq->timeout)
 242                 rq->timeout = q->sg_timeout;
 243         if (!rq->timeout)
 244                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 245         if (rq->timeout < BLK_MIN_SG_TIMEOUT)
 246                 rq->timeout = BLK_MIN_SG_TIMEOUT;
 247
 248         return 0;
 249 }
 250
 251 static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 252                                  struct bio *bio)
 253 {
 254         int r, ret = 0;
 255
 256         /*
 257          * fill in all the output members
 258          */
 259         hdr->status = rq->errors & 0xff;
 260         hdr->masked_status = status_byte(rq->errors);
 261         hdr->msg_status = msg_byte(rq->errors);
 262         hdr->host_status = host_byte(rq->errors);
 263         hdr->driver_status = driver_byte(rq->errors);
 264         hdr->info = 0;
 265         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
 266                 hdr->info |= SG_INFO_CHECK;
 267         hdr->resid = rq->resid_len;
 268         hdr->sb_len_wr = 0;
 269
 270         if (rq->sense_len && hdr->sbp) {
 271                 int len = min((unsigned int) hdr->mx_sb_len, rq->sense_len);
 272
 273                 if (!copy_to_user(hdr->sbp, rq->sense, len))
 274                         hdr->sb_len_wr = len;
 275                 else
 276                         ret = -EFAULT;
 277         }
 278
 279         r = blk_rq_unmap_user(bio);
 280         if (!ret)
 281                 ret = r;
 282         blk_put_request(rq);
 283
 284         return ret;
 285 }
 286
 287 static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 288                 struct sg_io_hdr *hdr, fmode_t mode)
 289 {
 290         unsigned long start_time;
 291         ssize_t ret = 0;
 292         int writing = 0;
 293         struct request *rq;
 294         char sense[SCSI_SENSE_BUFFERSIZE];
 295         struct bio *bio;
 296
 297         if (hdr->interface_id != 'S')
 298                 return -EINVAL;
 299         if (hdr->cmd_len > BLK_MAX_CDB)
 300                 return -EINVAL;
 301
 302         if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
 303                 return -EIO;
 304
 305         if (hdr->dxfer_len)
 306                 switch (hdr->dxfer_direction) {
 307                 default:
 308                         return -EINVAL;
 309                 case SG_DXFER_TO_DEV:
 310                         writing = 1;
 311                         break;
 312                 case SG_DXFER_TO_FROM_DEV:
 313                 case SG_DXFER_FROM_DEV:
 314                         break;
 315                 }
 316
 317         rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
 318         if (!rq)
 319                 return -ENOMEM;
 320         blk_rq_set_block_pc(rq);
 321
 322         if (blk_fill_sghdr_rq(q, rq, hdr, mode)) {
 323                 blk_put_request(rq);
 324                 return -EFAULT;
 325         }
 326
 327         if (hdr->iovec_count) {
 328                 size_t iov_data_len;
 329                 struct iovec *iov = NULL;
 330
 331                 ret = rw_copy_check_uvector(-1, hdr->dxferp, hdr->iovec_count,
 332                                             0, NULL, &iov);
 333                 if (ret < 0) {
 334                         kfree(iov);
 335                         goto out;
 336                 }
 337
 338                 iov_data_len = ret;
 339                 ret = 0;
 340
 341                 /* SG_IO howto says that the shorter of the two wins */
 342                 if (hdr->dxfer_len < iov_data_len) {
 343                         hdr->iovec_count = iov_shorten(iov,
 344                                                        hdr->iovec_count,
 345                                                        hdr->dxfer_len);
 346                         iov_data_len = hdr->dxfer_len;
 347                 }
 348
 349                 ret = blk_rq_map_user_iov(q, rq, NULL, (struct sg_iovec *) iov,
 350                                           hdr->iovec_count,
 351                                           iov_data_len, GFP_KERNEL);
 352                 kfree(iov);
 353         } else if (hdr->dxfer_len)
 354                 ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
 355                                       GFP_KERNEL);
 356
 357         if (ret)
 358                 goto out;
 359
 360         bio = rq->bio;
 361         memset(sense, 0, sizeof(sense));
 362         rq->sense = sense;
 363         rq->sense_len = 0;
 364         rq->retries = 0;
 365
 366         start_time = jiffies;
 367
 368         /* ignore return value. All information is passed back to caller
 369          * (if he doesn't check that is his problem).
 370          * N.B. a non-zero SCSI status is _not_ necessarily an error.
 371          */
 372         blk_execute_rq(q, bd_disk, rq, 0);
 373
 374         hdr->duration = jiffies_to_msecs(jiffies - start_time);
 375
 376         return blk_complete_sghdr_rq(rq, hdr, bio);
 377 out:
 378         blk_put_request(rq);
 379         return ret;
 380 }
 381
 382 /**
 383  * sg_scsi_ioctl  --  handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
 384  * @file:       file this ioctl operates on (optional)
 385  * @q:          request queue to send scsi commands down
 386  * @disk:       gendisk to operate on (option)
 387  * @sic:        userspace structure describing the command to perform
 388  *
 389  * Send down the scsi command described by @sic to the device below
 390  * the request queue @q.  If @file is non-NULL it's used to perform
 391  * fine-grained permission checks that allow users to send down
 392  * non-destructive SCSI commands.  If the caller has a struct gendisk
 393  * available it should be passed in as @disk to allow the low level
 394  * driver to use the information contained in it.  A non-NULL @disk
 395  * is only allowed if the caller knows that the low level driver doesn't
 396  * need it (e.g. in the scsi subsystem).
 397  *
 398  * Notes:
 399  *   -  This interface is deprecated - users should use the SG_IO
 400  *      interface instead, as this is a more flexible approach to
 401  *      performing SCSI commands on a device.
 402  *   -  The SCSI command length is determined by examining the 1st byte
 403  *      of the given command. There is no way to override this.
 404  *   -  Data transfers are limited to PAGE_SIZE
 405  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
 406  *      accommodate the sense buffer when an error occurs.
 407  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
 408  *      old code will not be surprised.
 409  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
 410  *      a negative return and the Unix error code in 'errno'.
 411  *      If the SCSI command succeeds then 0 is returned.
 412  *      Positive numbers returned are the compacted SCSI error codes (4
 413  *      bytes in one int) where the lowest byte is the SCSI status.
 414  */
 415 #define OMAX_SB_LEN 16          /* For backward compatibility */
 416 int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 417                 struct scsi_ioctl_command __user *sic)
 418 {
 419         struct request *rq;
 420         int err;
 421         unsigned int in_len, out_len, bytes, opcode, cmdlen;
 422         char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
 423
 424         if (!sic)
 425                 return -EINVAL;
 426
 427         /*
 428          * get in an out lengths, verify they don't exceed a page worth of data
 429          */
 430         if (get_user(in_len, &sic->inlen))
 431                 return -EFAULT;
 432         if (get_user(out_len, &sic->outlen))
 433                 return -EFAULT;
 434         if (in_len > PAGE_SIZE || out_len > PAGE_SIZE)
 435                 return -EINVAL;
 436         if (get_user(opcode, sic->data))
 437                 return -EFAULT;
 438
 439         bytes = max(in_len, out_len);
 440         if (bytes) {
 441                 buffer = kzalloc(bytes, q->bounce_gfp | GFP_USER| __GFP_NOWARN);
 442                 if (!buffer)
 443                         return -ENOMEM;
 444
 445         }
 446
 447         rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
 448
 449         cmdlen = COMMAND_SIZE(opcode);
 450
 451         /*
 452          * get command and data to send to device, if any
 453          */
 454         err = -EFAULT;
 455         rq->cmd_len = cmdlen;
 456         if (copy_from_user(rq->cmd, sic->data, cmdlen))
 457                 goto error;
 458
 459         if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
 460                 goto error;
 461
 462         err = blk_verify_command(rq->cmd, mode & FMODE_WRITE);
 463         if (err)
 464                 goto error;
 465
 466         /* default.  possible overriden later */
 467         rq->retries = 5;
 468
 469         switch (opcode) {
 470         case SEND_DIAGNOSTIC:
 471         case FORMAT_UNIT:
 472                 rq->timeout = FORMAT_UNIT_TIMEOUT;
 473                 rq->retries = 1;
 474                 break;
 475         case START_STOP:
 476                 rq->timeout = START_STOP_TIMEOUT;
 477                 break;
 478         case MOVE_MEDIUM:
 479                 rq->timeout = MOVE_MEDIUM_TIMEOUT;
 480                 break;
 481         case READ_ELEMENT_STATUS:
 482                 rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
 483                 break;
 484         case READ_DEFECT_DATA:
 485                 rq->timeout = READ_DEFECT_DATA_TIMEOUT;
 486                 rq->retries = 1;
 487                 break;
 488         default:
 489                 rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 490                 break;
 491         }
 492
 493         if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
 494                 err = DRIVER_ERROR << 24;
 495                 goto out;
 496         }
 497
 498         memset(sense, 0, sizeof(sense));
 499         rq->sense = sense;
 500         rq->sense_len = 0;
 501         blk_rq_set_block_pc(rq);
 502
 503         blk_execute_rq(q, disk, rq, 0);
 504
 505 out:
 506         err = rq->errors & 0xff;        /* only 8 bit SCSI status */
 507         if (err) {
 508                 if (rq->sense_len && rq->sense) {
 509                         bytes = (OMAX_SB_LEN > rq->sense_len) ?
 510                                 rq->sense_len : OMAX_SB_LEN;
 511                         if (copy_to_user(sic->data, rq->sense, bytes))
 512                                 err = -EFAULT;
 513                 }
 514         } else {
 515                 if (copy_to_user(sic->data, buffer, out_len))
 516                         err = -EFAULT;
 517         }
 518
 519 error:
 520         kfree(buffer);
 521         blk_put_request(rq);
 522         return err;
 523 }
 524 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
 525
 526 /* Send basic block requests */
 527 static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
 528                               int cmd, int data)
 529 {
 530         struct request *rq;
 531         int err;
 532
 533         rq = blk_get_request(q, WRITE, __GFP_WAIT);
 534         blk_rq_set_block_pc(rq);
 535         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
 536         rq->cmd[0] = cmd;
 537         rq->cmd[4] = data;
 538         rq->cmd_len = 6;
 539         err = blk_execute_rq(q, bd_disk, rq, 0);
 540         blk_put_request(rq);
 541
 542         return err;
 543 }
 544
 545 static inline int blk_send_start_stop(struct request_queue *q,
 546                                       struct gendisk *bd_disk, int data)
 547 {
 548         return __blk_send_generic(q, bd_disk, GPCMD_START_STOP_UNIT, data);
 549 }
 550
 551 int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mode,
 552                    unsigned int cmd, void __user *arg)
 553 {
 554         int err;
 555
 556         if (!q)
 557                 return -ENXIO;
 558
 559         switch (cmd) {
 560                 /*
 561                  * new sgv3 interface
 562                  */
 563                 case SG_GET_VERSION_NUM:
 564                         err = sg_get_version(arg);
 565                         break;
 566                 case SCSI_IOCTL_GET_IDLUN:
 567                         err = scsi_get_idlun(q, arg);
 568                         break;
 569                 case SCSI_IOCTL_GET_BUS_NUMBER:
 570                         err = scsi_get_bus(q, arg);
 571                         break;
 572                 case SG_SET_TIMEOUT:
 573                         err = sg_set_timeout(q, arg);
 574                         break;
 575                 case SG_GET_TIMEOUT:
 576                         err = sg_get_timeout(q);
 577                         break;
 578                 case SG_GET_RESERVED_SIZE:
 579                         err = sg_get_reserved_size(q, arg);
 580                         break;
 581                 case SG_SET_RESERVED_SIZE:
 582                         err = sg_set_reserved_size(q, arg);
 583                         break;
 584                 case SG_EMULATED_HOST:
 585                         err = sg_emulated_host(q, arg);
 586                         break;
 587                 case SG_IO: {
 588                         struct sg_io_hdr hdr;
 589
 590                         err = -EFAULT;
 591                         if (copy_from_user(&hdr, arg, sizeof(hdr)))
 592                                 break;
 593                         err = sg_io(q, bd_disk, &hdr, mode);
 594                         if (err == -EFAULT)
 595                                 break;
 596
 597                         if (copy_to_user(arg, &hdr, sizeof(hdr)))
 598                                 err = -EFAULT;
 599                         break;
 600                 }
 601                 case CDROM_SEND_PACKET: {
 602                         struct cdrom_generic_command cgc;
 603                         struct sg_io_hdr hdr;
 604
 605                         err = -EFAULT;
 606                         if (copy_from_user(&cgc, arg, sizeof(cgc)))
 607                                 break;
 608                         cgc.timeout = clock_t_to_jiffies(cgc.timeout);
 609                         memset(&hdr, 0, sizeof(hdr));
 610                         hdr.interface_id = 'S';
 611                         hdr.cmd_len = sizeof(cgc.cmd);
 612                         hdr.dxfer_len = cgc.buflen;
 613                         err = 0;
 614                         switch (cgc.data_direction) {
 615                                 case CGC_DATA_UNKNOWN:
 616                                         hdr.dxfer_direction = SG_DXFER_UNKNOWN;
 617                                         break;
 618                                 case CGC_DATA_WRITE:
 619                                         hdr.dxfer_direction = SG_DXFER_TO_DEV;
 620                                         break;
 621                                 case CGC_DATA_READ:
 622                                         hdr.dxfer_direction = SG_DXFER_FROM_DEV;
 623                                         break;
 624                                 case CGC_DATA_NONE:
 625                                         hdr.dxfer_direction = SG_DXFER_NONE;
 626                                         break;
 627                                 default:
 628                                         err = -EINVAL;
 629                         }
 630                         if (err)
 631                                 break;
 632
 633                         hdr.dxferp = cgc.buffer;
 634                         hdr.sbp = cgc.sense;
 635                         if (hdr.sbp)
 636                                 hdr.mx_sb_len = sizeof(struct request_sense);
 637                         hdr.timeout = jiffies_to_msecs(cgc.timeout);
 638                         hdr.cmdp = ((struct cdrom_generic_command __user*) arg)->cmd;
 639                         hdr.cmd_len = sizeof(cgc.cmd);
 640
 641                         err = sg_io(q, bd_disk, &hdr, mode);
 642                         if (err == -EFAULT)
 643                                 break;
 644
 645                         if (hdr.status)
 646                                 err = -EIO;
 647
 648                         cgc.stat = err;
 649                         cgc.buflen = hdr.resid;
 650                         if (copy_to_user(arg, &cgc, sizeof(cgc)))
 651                                 err = -EFAULT;
 652
 653                         break;
 654                 }
 655
 656                 /*
 657                  * old junk scsi send command ioctl
 658                  */
 659                 case SCSI_IOCTL_SEND_COMMAND:
 660                         printk(KERN_WARNING "program %s is using a deprecated SCSI ioctl, please convert it to SG_IO\n", current->comm);
 661                         err = -EINVAL;
 662                         if (!arg)
 663                                 break;
 664
 665                         err = sg_scsi_ioctl(q, bd_disk, mode, arg);
 666                         break;
 667                 case CDROMCLOSETRAY:
 668                         err = blk_send_start_stop(q, bd_disk, 0x03);
 669                         break;
 670                 case CDROMEJECT:
 671                         err = blk_send_start_stop(q, bd_disk, 0x02);
 672                         break;
 673                 default:
 674                         err = -ENOTTY;
 675         }
 676
 677         return err;
 678 }
 679 EXPORT_SYMBOL(scsi_cmd_ioctl);
 680
 681 int scsi_verify_blk_ioctl(struct block_device *bd, unsigned int cmd)
 682 {
 683         if (bd && bd == bd->bd_contains)
 684                 return 0;
 685
 686         /* Actually none of these is particularly useful on a partition,
 687          * but they are safe.
 688          */
 689         switch (cmd) {
 690         case SCSI_IOCTL_GET_IDLUN:
 691         case SCSI_IOCTL_GET_BUS_NUMBER:
 692         case SCSI_IOCTL_GET_PCI:
 693         case SCSI_IOCTL_PROBE_HOST:
 694         case SG_GET_VERSION_NUM:
 695         case SG_SET_TIMEOUT:
 696         case SG_GET_TIMEOUT:
 697         case SG_GET_RESERVED_SIZE:
 698         case SG_SET_RESERVED_SIZE:
 699         case SG_EMULATED_HOST:
 700                 return 0;
 701         case CDROM_GET_CAPABILITY:
 702                 /* Keep this until we remove the printk below.  udev sends it
 703                  * and we do not want to spam dmesg about it.   CD-ROMs do
 704                  * not have partitions, so we get here only for disks.
 705                  */
 706                 return -ENOIOCTLCMD;
 707         default:
 708                 break;
 709         }
 710
 711         if (capable(CAP_SYS_RAWIO))
 712                 return 0;
 713
 714         /* In particular, rule out all resets and host-specific ioctls.  */
 715         printk_ratelimited(KERN_WARNING
 716                            "%s: sending ioctl %x to a partition!\n", current->comm, cmd);
 717
 718         return -ENOIOCTLCMD;
 719 }
 720 EXPORT_SYMBOL(scsi_verify_blk_ioctl);
 721
 722 int scsi_cmd_blk_ioctl(struct block_device *bd, fmode_t mode,
 723                        unsigned int cmd, void __user *arg)
 724 {
 725         int ret;
 726
 727         ret = scsi_verify_blk_ioctl(bd, cmd);
 728         if (ret < 0)
 729                 return ret;
 730
 731         return scsi_cmd_ioctl(bd->bd_disk->queue, bd->bd_disk, mode, cmd, arg);
 732 }
 733 EXPORT_SYMBOL(scsi_cmd_blk_ioctl);
 734
 735 static int __init blk_scsi_ioctl_init(void)
 736 {
 737         blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
 738         return 0;
 739 }
 740 fs_initcall(blk_scsi_ioctl_init);